title: Purification, crystallization and preliminary crystallographic analysis of the SpaA backbone-pilin subunit from probiotic Lactobacillus rhamnosus GG.
abstract: Lactobacillus rhamnosus GG, a widely used Gram-positive probiotic strain, is clinically well known for its perceived health-promoting effects. It has recently been shown to display proteinaceous pilus fibres (called SpaCBA) on its cell surface. Structurally, SpaCBA pili possess a characteristic three-pilin polymerized architecture, with repeating SpaA major pilins that form the backbone and two types of minor subunits (SpaB and SpaC). In this study, recombinant SpaA protein was purified, characterized and crystallized. The crystals diffracted to a resolution of 2.0 Å and belonged to space group C2, with unit-cell parameters a=227.9, b=63.2, c=104.3 Å, β=95.1°.
authors.affiliation: Regional Centre for Biotechnology, 180 Udyog Vihar Phase 1, Gurgaon, Haryana 122 016, India.
authors.forename: Deepak
authors.initials: D
authors.lastname: Singh
authors.forename: Ingemar
authors.initials: I
authors.lastname: von Ossowski
authors.forename: Airi
authors.initials: A
authors.lastname: Palva
authors.forename: Vengadesan
authors.initials: V
authors.lastname: Krishnan
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray; D036781:Fimbriae Proteins / Q000737:chemistry* / Q000302:isolation & purification; D052201:Lacticaseibacillus rhamnosus / Q000378:metabolism*; D019936:Probiotics / Q000378:metabolism*; D021122:Protein Subunits / Q000737:chemistry*; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D021122:Protein Subunits; D011994:Recombinant Proteins; D036781:Fimbriae Proteins
keywords: Lactobacillus rhamnosus GG; SpaCBA pili; adhesion; bacterial surface proteins; fimbria; probiotics; sortase